How to Use TidePilot
Harmonic tide predictions for 12 major Indian ports — everything you need to plan tide-sensitive marine operations.
What is TidePilot?
TidePilot is a harmonic tide prediction tool covering 12 major Indian ports across Gujarat, the West Coast, East Coast, and Andaman & Nicobar Islands. It uses the standard 8-constituent harmonic method (M2, S2, N2, K2, K1, O1, P1, Q1) with published NHO India and Admiralty Tide Table constants.
All predictions run entirely in your browser — no server, no internet required after the page loads. Times are displayed in IST (UTC+5:30) throughout.
TidePilot is intended as a planning aid. For safety-critical navigation, always verify against the current official NHO India Annual Tide Tables.
The Seven Views
Today's full 24-hour tide curve for any of the 12 ports. Shows the live current water level, a countdown to the next High Water or Low Water, and the tidal phase. Use the date arrows to browse past or future days.
Detailed tide chart for a single chosen date. Pick any port and any date to get the precise HW/LW times and heights, the tidal phase badge, and an interactive curve you can hover for height at any hour.
A 7-day planner showing all HW/LW events for each day of the week. Ideal for scheduling berthing windows, dredging operations, or crew transfers across a work week. Navigate week-by-week with the arrows.
Full month table with every HW/LW event, plus three key statistics at the top — Peak High Water, Lowest Low Water, and Spring Tide days. Good for monthly planning, cargo scheduling, and vessel arrival windows.
Yearly overview with HAT and LAT (Highest and Lowest Astronomical Tides), a month-by-month summary, and a Shipbuilding & Dry-Dock Planning Guide that highlights the best months for launching, keel laying, and trials at each port.
Side-by-side comparison of two ports on the same day. Both tide curves overlay on one chart (teal vs indigo), and HW/LW events are listed in two columns. Use this to coordinate multi-port convoy movements or transfers.
Set personal reminders for tide-sensitive events — drydock entry, cargo loading, vessel departure, sea trials, and more. Upcoming reminders appear as a strip on the Home page. All data is stored locally in your browser.
Reading the Tide Chart
Tidal Phases Explained
New or full moon — maximum tidal range. Highest HW, lowest LW. Best for deep-draught vessel access.
1–2 days either side of spring. Range still large, approaching or leaving maximum.
Midway between spring and neap. Moderate range — average planning conditions.
1–2 days from neap. Range is shrinking or growing toward neap tides.
Quarter moon — minimum tidal range. Smallest HW/LW difference. Preferred for harbour maintenance, berthing of shallow-draught vessels.
Phase is calculated from lunar cycle position — 0 = New Moon (spring), 0.25 = First Quarter (neap), 0.5 = Full Moon (spring), 0.75 = Last Quarter (neap).
Port Coverage
| PORT | REGION | SPRING RANGE | NOTE |
|---|---|---|---|
| Dahej | Gujarat | 7.6 m | NHO secondary port, extreme range |
| Bhavnagar | Gujarat | 8.2 m | NHO reference port, highest range |
| Hazira | Gujarat | 5.6 m | Gulf of Khambhat south entry |
| Kandla | Gujarat | 4.2 m | Gulf of Kutch |
| Mumbai | West Coast | 4.3 m | Apollo Bunder reference station |
| Mormugao | West Coast | 2.3 m | Goa |
| Kochi | West Coast | 0.9 m | Mixed diurnal, small range |
| Chennai | East Coast | 1.4 m | Semidiurnal, small range |
| Vizag | East Coast | 1.1 m | Visakhapatnam |
| Paradip | East Coast | 2.3 m | Odisha |
| Kolkata | East Coast | 4.7 m | Hooghly River amplification |
| Port Blair | Islands | 1.9 m | Andaman & Nicobar |
Glossary
Planning Tips
For vessel arrival planning, use the Monthly view to find spring tide windows with the highest HW, then drill into Daily for exact times.
For drydock or slipway operations, Annual shows the best months by port. Spring tides give maximum tidal drop for dry-docking.
Use Compare to check if two ports have HW at similar times — useful for coordinating multi-port convoy schedules.
Gulf of Khambhat ports (Dahej, Bhavnagar) have India's largest tidal ranges (7–9 m spring). Always verify keel clearance before entry.
Set a Reminder for your drydock date or sea trial window so it shows up on the Home page countdown.
Toggle between 24h and 12h time format using the "24h / 12h" button in the top-right of the navbar.
Tide predictions are harmonic — they use published NHO and Admiralty constants. For safety-critical navigation, always cross-check with the official NHO India Annual Tide Tables.